Constructing Z-Scheme Bi2O3/In2O3 Heterojunction for Efficient Photocatalytic Degradation of Rhodamine B

A Bi 2 O 3 /In 2 O 3 heterojunction is successfully fabricated via a facile hydrothermal method using sodium bismuthate and indium nitrate as the source materials. The crystal structure, composition, micromorphology, and optical property of the Bi 2 O 3 /In 2 O 3 heterojunction are analyzed by X-ray diffraction, X-ray photoelectron spectroscopy, Fourier transform infrared spectrum, scanning electron microscopy, transmission electron microscopy, and solid ultraviolet-visible (UV-vis) diffuse reflectance spectra. The Bi 2 O 3 /In 2 O 3 heterojunction exhibits a remarkable photocatalytic degradation capacity for Rhodamine B, which is better than that of pure Bi 2 O 3 and In 2 O 3 . The photogenerated charges separation and transfer process of the Bi 2 O 3 /In 2 O 3 heterojunction follows a direct Z-scheme mechanism under UV–vis light irradiation. The trapping experiment indicates that oxidative radicals including •OH, h + , and •O 2 − play crucial roles in the photodegradation process. The outstanding photodegradation capacity is ascribed to spatially separated charge carriers, fast-charge transportation characteristic, and special bandgap structure of the Bi 2 O 3 /In 2 O 3 heterojunction. The introduction of H + and OH − ions into the reaction system promotes the formation of •OH and •O 2 − radicals, significantly enhancing the photodegradation rate of RhB. This study presents a new insight into the construction of the Z-scheme Bi 2 O 3 /In 2 O 3 heterojunction photocatalyst with potential application in wastewater treatment.